NEW YORK (CBSNewYork/AP) — Long Island Rep. Peter King said the FBI would have carried out a much more intense investigation of two men now suspected in the Boston Marathon bombings if the Russians had informed Washington of the “radicalization” of Tamerlan Tsarnaev and his mother.

King, a member of the House Homeland Security Committee, said such information “definitely would have caused the investigation to go further.”

“How often do you find someone having three separate coincidences regarding possible terrorist activity,” King told the “Today” show.

King said he worries about limits on Moscow’s cooperation with Washington in the case, saying “there’s a bit of a dance here.”

The congressman said Moscow doesn’t want to reveal information “that gives us an idea of how they do their intelligence” work, their sources and methods.

King also said it’s difficult to believe that two people could have executed the Boston bombings alone.

“Too much of it was perfectly synchronized here for this just to be two guys doing this on their own,” he said. “I believe there had to be some sort of facilitation at least, possible co-conspirators but certainly other people involved.”

The chairman of the House Homeland Security Committee, Rep. Michael McCaul, said he also thinks the mother of Tamerlan and Dzhokhar Tsarnaev played “a very strong role” in her sons’ radicalization process.

He told “Fox News Sunday” the shrapnel-packed pressure cooker bombs used in the attacks leads him to believe that someone did train the bombers.

Several lawmakers have been questioning what more could have been done to prevent the Boston bombings, which killed three people and left hundreds more wounded.

Standing in Times Square on Sunday, Sen. Charles Schumer said serious questions remain about what the FBI knew about the suspects.

“They may have messed up because Russia did call and say they have doubts about Tsarnaev,” Schumer said. “A foreign country says ‘this person’s dangerous.’ They interview him, as they should, they found nothing. He then goes back to his homeland and immediately on coming back puts all this inflammatory stuff on his website. It seems pretty logical that the FBI should have interviewed him again.”

“The FBI is bound by law,” explained CBS News senior correspondent John Miller, on “Face the Nation” Sunday. “And they did a 90-day assessment on this, which means they investigated this guy for three months. But after that, the rules say, if you don’t find something that’s not covered by the first amendment or that’s going to lead you somewhere else, you have to close that out.”

Schumer has called for federal hearings into the matter to determine what the FBI did and did not know about the brothers.

Tamerlan Tsarnaev was killed in a shootout with police. His brother is recovering from injuries at a military lockup.